The present invention relates to a thin-plate supporting container designed for the housing, storage and transportation of thin plates, such as semiconductor wafers, storage disks, liquid crystal glass substrates, and the like.
As an example of a conventional container having an easily attachable/detachable lid, the container disclosed in the Japanese Utility Model Publication No. Hei 6-13114 (No. 13114/1994) entitled xe2x80x9cEngagement Mechanism in Sealed Containerxe2x80x9d is known.
Referring to FIGS. 2 through 4, the sealed container 51 generally includes a container body 52, and a lid 53 for covering an open top of the container body 52. Each of opposing side walls of the lid 53 is provided with an engagement piece 54 extending downward. Each engagement piece 54 has an operational hole 55 formed at the center thereof, and engagement apertures 56 formed at the both sides of the operational hole 55. In the container body 52, there are provided engagement elements 57 which engage with the engagement apertures 56 formed in the engagement piece 54. Each engagement element 57 has an inclined surface 57A which slidably contacts with and spreads outwardly the engagement piece 54.
In the above construction, when the lid 53 is placed on the container body 52 and pressed downward from above, the engagement piece 54 slidably contacts with the inclined surface 57A and is spread outwardly, so that the engagement elements 57 engage with their corresponding engagement apertures 56. Thereby, the lid 53 is attached to the container body 52 so that they are securely fastened to each other.
When the lid 53 is removed from the container body 52, the engagement pieces 54 are bent. Specifically, the operator inserts his hands into the operational holes 55 of the two engagement pieces 54 and bends the engagement pieces 54 in directions in which the pieces 54 are pulled away from each other (toward the right in FIG. 4) so as to disengage the engagement apertures 56 of the engagement pieces 54 from their corresponding engagement elements 57. Thereafter, the lid 53 is removed from the container body 52.
In the interior of the container body 52, there may be provided thin-plate supporting units (not shown) which are formed as an integral part of an inner surface of the container body 52 and adapted to support at a predetermined spacing a plurality of semiconductor wafers housed in the container body 52, or there may be housed a wafer carrier serving as a separate member.
Meanwhile, when the lid 53 is removed from the container body 52, the two engagement pieces 54 must be bent in directions in which the pieces 54 are pulled away from each other so as to disengage the engagement apertures 56 of the engagement piece 54 from their corresponding engagement elements 57.
However, such operations are difficult to perform. This is because in the operation of lifting the lid 53 upward while bending the two engagement pieces 54 in directions in which the pieces 54 are pulled away from each other, the operator must perform an operation of pulling the engagement pieces 54 away from each other and an operation of lifting the lid 53 upward at the same time.
Further, due to complexity of these operations, it has been difficult to automate these operations by means of transfer equipment.
Further, when the sealed container needs to be washed after use, if the container is of a type in which the thin-plate supporting unit is integrally formed in the container body 52, washing the sealed container is not an easy task. Specifically, since the thin-plate supporting unit has a plurality of narrow slots for receiving the thin plates, besides being formed in the interior of the sealed container, it is difficult to wash the sealed container to an extent that the innermost portions of the slots are thoroughly washed. This problem also arises in the case of a wafer carrier.
The present invention is accomplished in view of the above-mentioned problems. An object of the present invention is to provide a thin-plate supporting container in which the operations of attaching and detaching the lid and the operation of washing the container are simplified.
A thin-plate supporting container according to a first aspect of the invention is characterized in that there are provided a container body for housing therein a plurality of thin plates; and thin-plate supporting units, provided on opposing side walls of the container body, for supporting the thin plates thus housed from their both sides, wherein
there are provided: a lid for covering the container body; and an easy attach/detach mechanism for causing the lid to be attached to and detached from the container body,
the easy attach/detach mechanism including:
an engagement part provided at a circumferential portion of the lid;
an object engagement part which is provided on the container body in such a manner as to oppose the engagement part and adapted to engage with the engagement part so as to secure the lid to the container body;
an arm which is provided integrally with the engagement part of the lid and adapted to release the engagement part from the object engagement part when the arm is pressed; and
an elevating mechanism for slightly elevating the lid from the container body when the engagement part is released from the object engagement part by means of the arm.
In this construction, when the lid is attached to the container body, the container body is placed in an upright position with its open top directed upward, and the open top is covered with the lid, and then the lid is pressed from above. Thereby, the engagement part of the easy attach/detach mechanism engages with the object engagement part, so that the lid is secured to the container body. When the lid is removed, the arm is pressed down ward. Thereby, the engagement part disengages from the object engagement part, so that the lid having been secured to the container body is released therefrom, whereby the lid is slightly elevated by means of the elevating mechanism. As a result, the lid is released from the container body. Thereafter, the lid is lifted manually by the operator, or automatically by the transfer equipment.
The thin-plate supporting container according to a second aspect of the present invention is characterized in that, in the thin-plate supporting container of the first aspect of the present invention, there are provided:
a leg, provided at the lower portion of the container body, for stably supporting the container body placed in an upright position; and
a leg receiving part, formed on the upper surface of the lid, for receiving the leg.
In this construction, when the thin-plate supporting container is placed in an upright position, the leg of the container body abutting contacts with the placement surface so that the thin-plate supporting container is supported in a stable manner. When a plurality of thin-plate supporting containers are stacked in a plurality of decks, the leg of the container body fits into the leg receiving part formed on the upper surface of the lid. Thereby, a plurality of thin-plate supporting container are stacked in a stable manner.
A thin-plate supporting container according to a third aspect of the present invention is characterized in that there are provided a container body for housing therein a plurality of thin plates; and thin-plate supporting units, provided on opposing side walls of the container body, for supporting the thin plates thus housed from their both sides, wherein the thin-plate supporting unit is detachably mounted to the container body.
In this construction, when the thin-plate supporting unit, which is detachably mounted to the container body, is detached, the thin-plate supporting unit and the container body can be washed easily and sufficiently to every small portion thereof.
Further, in this construction, the operator can previously prepare, with respect to the thin-plate supporting unit, a plurality of types in which the number of thin plates to be supported, the spacing between the thin plates to be housed, and the distance between the two thin-plate supporting units oppositely provided are appropriately varied, and can select an appropriate type suitable for the dimension, the number, and the other features of the thin plates to be housed. Thus, the operator can easily and swiftly cope with various situations where the container is used.
The thin-plate supporting container according to a fourth aspect of the present invention is characterized in that, in the thin-plate supporting container according to the third aspect of the present invention,
each of the thin-plate supporting units includes:
a plurality of ribs which are provided in parallel at a predetermined spacing, and adapted to support the plurality of thin plates individually;
supporting bars which are integrally connected to and whereby support the ribs, which are in the state that are provided in parallel at a predetermined spacing, at least at an innermost position and at an inlet-side position;
V-shaped groove each of which is formed on an abutting contact surface of the supporting bar of the innermost position, the abutting contact surface serving to abutting contact with the thin plate, and adapted to guide, when the container body is placed in an upright position, the thin plate to the center between the ribs so as to support the thin plate at the innermost position.
In this construction, each thin plate is inserted between neighboring ribs of the thin-plate supporting unit. When the thin-plate supporting container is placed in a horizontal position and its open top is directed sideward, each thin plate is placed on and supported by each rib. When the thin-plate supporting container is placed in an upright position, each thin plate is mainly placed on and supported by the region of the thin plate near the innermost supporting bar. Specifically, since a V-shaped groove is formed at the region of the rib near the innermost supporting bar, the inserted thin plate is guided by the inclined surface of the V-shaped groove to fall into the bottom of the groove, so that the thin plate is supported by the innermost supporting bar region of the thin plate while being situated at the position intermediate between neighboring ribs. The upper portions of individual thin plates are supported by the upper portions of each rib. Accordingly, the thin plates are prevented from interfering with each other.
The thin-plate supporting container according to a fifth aspect of the present invention is characterized in that, in the thin-plate supporting container according to the fourth aspect of the present invention, the thin plate is disk-shaped, and the rib is formed in the shape of a circular arc along the circumference of the disk-shaped thin plate, the thin plate and the rib overlapping each other at a small area along the circumference of the thin plate.
In this construction, when the individual disk-shaped thin plates are inserted between neighboring ribs of the thin-plate supporting unit, each rib supports each thin plate along the circumferential edge of the thin plate in such a manner that the rib and the thin plate contact with each other at a small area. Thereby, the area in which the rib and the thin plate overlap each other is reduced, so that rib is prevented from adversely affecting the surface of the thin plate. Specifically, the synthetic resin forming the rib generates a trace amount of gas. However, the rib and the thin plate overlap each other at a small area, and therefore the gas thus generated rarely contacts the surfaces of the thin plates. Thereby, the adverse effect caused by the gas and applied to the surfaces of the thin plates are reduced to the smallest extent.
Further, as the area in which the ribs overlap each other seen from the direction perpendicular to the flats of the ribs is reduced, the dust or the like that adheres on the surfaces of the ribs is also reduced, and moreover washing of the ribs becomes easy.
A thin-plate supporting container according to a sixth aspect of the present invention is characterized in that, in the thin-plate supporting container according to the third aspect of the present invention,
the thin-plate supporting units are made of a synthetic resin which is excellent in formability and can be finished at a high precision in dimension.
In this construction, the thin plates are securely supported by thin-plate supporting unit having high dimensional precision, and interference between neighboring thin plates is prevented from occurring. Examples of the synthetic resin forming the thin-plate supporting unit includes PBT (polybutylene terephthalate), PEEK (polyetheretherketone), PBN (polybutylene naphthalate), and the like.
A thin-plate supporting container according to a seventh aspect of the present invention is characterized in that, in the thin-plate supporting container according to the first aspect of the present invention, a top flange to be gripped by the arm of transfer equipment, and a carrying handle are detachably attached to the container body.
In this construction, when the thin-plate supporting container is used, the top flange and the carrying handle are attached so that the container can be transported automatically by the transfer equipment or manually carried by the operator. When the thin-plate container is transported, the top flange and the carrying handle are detached and packed in a compact size.
A thin-plate supporting container according to an eighth aspect of the present invention, is characterized in that, in the thin-plate supporting container according to the seventh aspect of the present invention, the carrying handle is attached in such an inclined position as to be oriented in the direction intermediate between the vertical and horizontal directions of the container body.
In this construction, when the operator changes the position of the thin-plate container body from an upright position to a horizontal position, or from a horizontal position to an upright position, with the handle in his hand, he does not need to turn his wrist to an extreme extent, so that operability of the container is enhanced.
A thin-plate supporting container according to a ninth aspect of the present invention characterized in that, in the thin-plate supporting container according to the first aspect of the present invention, wherein there is provided a filter, provided on either one of the container body and the lid, for allowing gas to pass therethrough so as to equalize the internal and external pressures while inhibiting dust or the like from passing therethrough.
In this construction, when the container is transported by plane and the atmospheric pressure around the container changes greatly, the filter allows gas to pass therethrough between the inside and outside of the thin-plate container so that the internal atmospheric pressure of the container is always kept to the same value. In other words, the internal atmospheric pressure of the container is adjusted to its optimum value while preventing dust or the like from entering the thin-plate supporting container and keeping the internal air clean. Thereby, the lid is prevented from becoming difficult to open.
Further, since the lid is detachably attached, when the thin-plate supporting container is washed, the filter can be detached and washing the container can be performed in an efficient manner.